| 摘要 |
PROBLEM TO BE SOLVED: To decrease consumption power of an electric motor and increase start torque of an electric motor at the same time by controlling input current according to increase of rotating speed of the electric motor. SOLUTION: The electric motor 12 is connected to a compressor main body (not illustrated) for compressing air taken from an outside, and the compressor main body is driven by the electric motor 12. The electric motor 12 is composed of a reluctance motor, and a power feeding control device constituted by a power-feeding unit 23 and an inverter control unit 31 is connected to the electric motor 12. A rotation position detector 19 for detecting rotating speed of the electric motor 12 is connected to the inverter control unit 31. In the inverter control unit 31, the electric motor 12 is driven by a three-phase electrifying control when the electric motor 12 is started, and input current is restricted according to motor angle speed at the time of start. After rotating speed of the electric motor 12 attains set rotating speed, the electric motor 12 is driven by means of two-phase electrifying control. |
